Journal of Advanced Veterinary Research

Impact of pH and temperature on Plantacirin C against Escherichia coli O157:H7 and Staphylococcus aureus and its gene expression.

Eman Gad

The aim of this study is to investigate the inhibitory effect of plantacirin C, the predominant bacteriocin produced by Lactobacillus plantarum (L. Plantarum), in traditional dairy products (milk, cheese, and yogurt) from Assiut city in Upper Egypt against Escherichia coli O157:H7 and Staphylococcus aureus. It also examined the effect of temperature (40°C, 4°C) and pH (4 and 7) on plantacirin C gene expression. The research was conducted from October 2021 to April 2022 in various localities within Assiut Governorate, Egypt. L. Plantarum was isolated from milk products and identified using microbiological and molecular techniques. Plantacirin C's activity was detected by use of the well diffusion method.. The effect of pH on bacteriocin production was determined and adjusted to pH 4 and 7 Subsequently, pH effect and temperature on plantacirin C gene expression was determined. RNA extraction from L. Plantarum strains was performed, followed by cDNA synthesis. Real-time PCR amplification was then carried out. The results showed that the effect of L. Plantarum bacteriocin at 4°C and 40°C was higher on Staph. aureus than on E. coli, with a count of 1.5 × 10⁷ CFU/mL. Real-time PCR using 16S rRNA primer for total bacteria and plantacirin C primer revealed that the effect of plantacirin C gene increased at 40°C (with increasing temperature), while the effect of plantacirin C gene decreased at pH 4 (with increasing acidity).

Detection of Aflatoxin and Novel Simplest Regimes for its Detoxification in Milk and Soft Cheese

Doaa Safwat Abdel-Maguid

Sixty samples of marketable milk and soft cheese (locally manufactured) were randomly collected from El-kharja markets, New Valley governorate, Egypt. Aflatoxin (AFs) was detected in the samples quantitatively utilizing ELISA analysis. The positive results (tainted with AFs) indicated a 100% excess of the allowable limit. Furthermore, locally manufactured soft cheese had higher AFM1 contamination than marketable milk. Additionally, the experimental trials to treat contaminated milk with microwave heating, Mish contaminated samples with lemon, and Kareish cheese with carbonated water revealed 9.4, 43.9, and 54.9% decline AFs, respectively.

Significant impact of physicochemical water parameters in tilapia aquculture

Hosnia Swafy Abdel-Mohsein

Water quality is an important part of any aquaculture system. Water provides aquatic animals with oxygen, allows for waste removal, and is the conduit for their food. Similar to all other organisms, fish are heavily influenced and dependent on the characteristics of their environment. Non-optimum water physicochemical parameters as dissolved oxygen, pH, salinity, ammonia, temperature etc. can cause stress to the cultured fish and thus make them more susceptible to disease outbreaks. Nile tilapia is the most cultured fish in Egypt. While it’s sustainable production is hindered by many obstacles. One of them is the water quality, therefore the hygienic effects of the water parameters are important to be clear in culturing.

Evaluation of Various Endometritis Diagnostic and alternative Therapeutic Approaches in Arabian Mares

Mohammed ali

Herein, the purpose of this study was to assess the reliability of various approaches for the diagnosis and management of endometritis in Arabian mares. Mares (n = 55) were subjected to a body condition score, perineal conformation, and an ultrasonography examination. Moreover, collection of direct uterine swabs and swabs from low-volume lavage as well as endometrial biopsy. Mares (n = 23) were randomly selected for three different intrauterine treatment regimens. Mares were serviced in the next estrus after the treatment. Results indicated that the proportion of abnormal vulval conformation increased as the age of the animals increased, along with a low body score. Bacteria and fungi were isolated from 83.64% of mares. Fungi were isolated from 5.5% of mares. E. coli (n = 21; 36.8%) was the most isolated bacterium, followed by Staphylococcus spp. (n = 10; 17.5%) and Beta-hemolytic Streptococcus spp. (n = 8; 14.03%). Direct swabs were positively coincident in 36% with low-volume uterine lavage. Bacteriological and ultrasonography examinations contradicted in 71% of the cases (P < 0.05), while bacteriological and biopsy findings matched in 86.2% of the cases (P < 0.05). Swabs from low-volume lavage were more reliable than direct swabs in the diagnosis of endometritis. Cytological findings agreed with ultrasonography examination, while ultrasonography findings disagreed with biopsy grade in endometritis diagnosis (P < 0.05). Cytological, microbiological, and sonographic examinations were as sensitive and specific as histopathological examinations. The conception rates of mares treated with an intrauterine infusion of penicillin + gentamicin sulfate, ceftiofur sodium, and cephapirin were 75%, 50%, and 28.6%, respectively. In conclusion, cytological and bacteriological assessment of the endometrium, along with an ultrasonography examination, could be used with a high degree of confidence to diagnose endometritis in the mare without the need for an endometrial biopsy. Although there is a low conception rate with one intrauterine infusion of cephapirin (Metricure®), it could be used successfully as a one-time intrauterine therapy in mares suffering from endometritis.

Attempts for improving mycological quality of chicken carcasses

ghada atya

Seventy five chicken carcasses were divided into 5 groups (15 for each) and packed into plastic bags after sprayed with water, potassium sorbate (2%, 2.5%) and natamycin (0.1% and 0.2%). The samples were stored in refrigerator at 4⁰c and examined after 24 hours to study the effect of such treatments on their mycological profile. potassium sorbate (2%, 2.5%) and natamycin (0.1%, 0.2%) reduced mold counts from 3.14 x 10⁴ ± 0.27 x 10⁴ in control group to 9.62 x 10³± 1.15 x 10³, 5.47 x 10³ ± 0.49 x 10³, 2.81 x 10³ ± 0.22 x 10³ and 8.75 x 10² ± 0.64 x 10², respectively. A higher reduction percent in the total mold counts by using of natamycin (0.1% and 0.2%) were 91.1 % and 97.2%. While, lower reduction percent in the total molds count by using of potassium sorbate (2% and 2.5%) were 69.4% and 82.6%, respectively. Aspergillus species isolated from control group were A. flavus (40%), A. fumigatus (6.7%), A. niger (13.3%), A. ochraceus (13.3%) and A. tereus (6.7%), from potassium sorbate (2%) A. flavus (33.3%), A. fumigatus (6.7%), A. niger (13.3%), A. ochraceus (6.7%) and A. tereus (6.7%) were isolated and identified, In potassium sorbate (2.5%) group, the isolation percentage of A. flavus, A. niger, A. ochraceus and A. tereus were 20%, 13.3%, 6.7% and 6.7%, respectively, in natamycin (0.1%) group A. flavus (20%), A. niger (6.7%) and A. ochraceus (6.7%) and in natamycin (0.2%) group were A. flavus (13.3%) and A. niger (6.7%). Toxigenic A. flavus isolated from control, potassium sorbate (2%), potassium sorbate (2.5%) and natamycin (0.1%) treated groups were 26.7%, 26.7%, 13.3% and 6.7%, respectively but there are no toxigenic strains of A. flavus isolated from 0.2% Natamycin treated group. Aflatoxins B1, B2, G1 and G2 were extracted from control and potassium sorbate (2%) groups but B1 and B2 were extracted from potassium sorbate (2.5%) group. While, in 0.1% Natamycin group B1 is the only aflatoxin that extracted. Generally, natamycin proved to be more efficient than potassium sorbate in suppression of mold growth in chicken carcasses and higher concentrations are better. So, the use of natamycin (0.2 %), as it is safe antifungal agent, is recommended to improve safety of chicken carcasses.